<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }
        
        body,
        html {
            height: 100%;
        }
        
        body {
            /* 手机网页 apple-system */
            font-family: -apple-system-font, sans-serif;
            background-color: #111;
        }
        
        .page {
            position: absolute;
            top: 0;
            right: 0;
            bottom: 0;
            left: 0;
            overflow-y: auto;
            -webkit-overflow-scrollin于g: touch;
        }
        
        .page__hd {
            height: 200vh;
            /*相对viewport单位 视窗*/
        }
    </style>
</head>

<body>
    <div class="page">
        <div class="page__hd">
            <div class="page__title">Flex</div>
            <div class="page__desc">Flex布局</div>
        </div>
        <div class="page__bd padding__bd__spacing">
            <div class="weui-flex">
                <div class="weui-flex__item">
                    <div class="placeholder"></div>
                </div>
            </div>
        </div>
    </div>
</body>

</html>